Patent GB-514048-A (GB)
Title: Improvements in or relating to apparatus for truing grinding and abrasive wheels
IPC: B24B53/00
Filed: 1938-04-11
Abstract: 514,048. Trueing grinding wheels. KAPELLA, Ltd., and COOKE, E. A. April 11, 1938, No. 11015. [Class 60] Apparatus for trueing grinding-wheels having a profiled operative face, for example, in a copying machine wherein a pantograph arrangement A<2>, and a grinding wheel B as described in Specification 481,658 are employed, comprises an arm C<1> pivoted to the machine frame at C<2> to enable the trueing diamond to be brought up to, or moved away from the wheel, a clamp C<9>, C<10> being used to lock the arm C' in either position and a stop C' being used for determining the working position. On the arm C' is slidably adjustable, by a screw C<6>, a bracket C<4> in which is journalled on a hollow pivot pin C<3> the axis E<1> of which is a primary axis, a primary link D'. A secondary link D<2> is pivoted, on a secondary axis E<2> on the link D', the link D' having thereon a follower F and a guide D<2>, pivotally adjustable about the axis D<5> of the follower and having adjustable thereon, by a screw D', or a wedge, a holder D' for a diamond D; the diamond is adjustable in the holder by a screw D<9>. The primary link has thereon an extension F<5>. carrying an operating knob F<2> and having therein a stud F<4> by which the links D', D<2> may be locked together; the link D<2> also has thereon operating knobs F'. The follower F is adapted to engage and be moved along either of two fences F' adjustably mounted on blocks F', which are adjustable in a part circular way F' on the bracket C<4>. The primary axis E<1> is located in the primary or working plane A<10> of the machine by the use of a microscope A', the graticule of which carries two scales A<12>, A<13>, and three angles A<11>, these angles being employed for setting the fences when a grinding wheel having a V-shaped periphery is to be . trued; the rounded edge of the V is formed by locking the links D<1>, D<2> together by the stud F<4> and swinging them round the axis E', which has been set to the centre of the rounded edge. Straight line movement of the diamond is ensured by making the length of the links D<1>, D<2> and the distance from the axis E<2> to the diamond point all equal, and curved, or combined curved and straight profiles may be produced by adjustment of the fences and the diamond. In order to illuminate the edge of the grinding wheel during observations through the microscope A<6>, a housing G is provided on the bracket C<4> for a lamp G<2>, and a tube G<3> having therein a collimating lens G' and a 45 degrees mirror G<7> is mounted on the housing; the housing is movable from and into position by a handle G<9>. In a modification, for example for tracing multi-profile grinding wheels for screw threads, the tracing unit is adjustable transversely of the plane of rotation of the grinding wheel by means of a screw; this construction also may be used for trueing profiles of stepped form. In a further modification, two diamonds are employed, mounted as described above, for operating one on each side of the wheel, the movements of the diamonds being out of phase, and a third diamond is employed for the curved edge. Specifications 480,584, 480,661, 480,663 and 480,668 also are referred to.